Water cooled grinding wheel



5 1955 J. A. HARRINGTON 2,722,792

WATER COOLED GRINDING WHEEL Filed June 22, 1953 IN V EN TOR.

170722 A. Zikrrwgiaz 4 AN'yj' United States Patent 2,722,792 p WATER COOLED GRINDING WHEEL John A. Harrington, Minneapolis, Minm, assignor' to Continental Machines, Incorporated, Savage, Minn, a corporation of Minnesota 7 Application June 22, 1953, Serial No. 363,033

7 Claims. (Cl. 51-267) My. present invention relates to improved .means for 2,722,792 Patented Nov. 8, 1955 vided with an integrally formed threaded stud 9 equipped with a suitable retaining nut and washer assembly 10.

.The inner end of the hub structure 6 is formed to provide a radial stop flange 11, which engages the inner flat surface of the grinding wheel 1. The outer end portion of the hub structure 6 projects somewhat beyond the delivering liquid coolant, generally water, to surfaces of Y grinding wheels spaced from the working surfaces thereof for delivery to the latter through the porous bodies relates to improved means for delivering liquid coolant to the peripheral working surfaces of relatively wide or axially long grinding wheels in such manner that the entire working surfaces of such wheels will receive a substantially equal amount of coolant.

A specific object of the invention is the provision of an improved mounting structure for porous grinding wheels, which is constructed and arranged to receive liquid coolant and distribute the same to a surface of the grinding wheel defining the axial mounting bore thereof at numerous points so spaced axially and circumferentially thereof that the said coolant will be delivered uniformly by centrifugal action to the working peripheral surface of the porous grinding wheel.

A further object of the invention is the provision of a device of the class described above which is inexpensive to produce, highly efficient in operation, and durable of contsruction.

A still further object of the invention is the provision of a device of the class described which is suitable for mounting directly upon the tapered end portion of a power-driven shaft, such as is conventionally employed for the mounting and driving of grinding wheels.

The above and other highly important objects and advantages of the invention will be made apparent from the following specification, claims and appended drawmgs.

In the accompanying drawings, like characters indicate like parts throughout the several views.

Referring to the drawings:

Fig. 1 is a fragmentary view in side elevation, with some parts broken away and some parts shown in section, of a conventional porous grinding wheel mounted on a liquid coolant receiving and distributing mounting hub, built in accordance with the invention; and

Fig. 2 is an axial sectional view taken on the line 2-2 of Fig. 1.

In the drawings, a conventional, but nevertheless wider than usual, porous grinding wheel is indicated by 1. This grinding wheel 1 has a cylindrical peripheral working surface 2 and an axial bore 3. The grinding wheel 1 is mounted on the tapered end portion 4 of a suitably journalled power-driven shaft 5 through the medium of an improved mounting hub structure 6 built in accordance with the instant invention. This mounting hub structure has a cylindrical outer surface 7, which is snugly received in the bore 3 of the grinding wheel and has an axial bore 8 tapered to correspond to the taper of the outer portion 4 of shaft 5 and snugly receiving the latter. For the purpose of tightly clamping the mounting hub structure 6 on the tapered portion of shaft 5, the said shaft 5 is proouter flat face of the grinding wheel and is externally threaded to receive an internally threaded clamping nut 12, which is opposed to the hub flange 11 and anchors the grinding wheel to the hub structure for common rotation therewith.

a The improved hub structure 6 is formed at its radially intermediate portion to define a pair of opposed axially outwardly opening internal annular channels or chambers 13. These internal annular channels 13 are spaced apart adjacent the axial center of the hub structure to provide a rigid connecting web 14 between the radially inner and radially outer portions of the hub structure.

.The portions of the hub structure defining the radially outer walls of the annular channels 13 are formed to define radially inwardly opening circular channels 15. In accordance with the present examples, there are three of these radially inwardly opening channels 15 for each of the channels 13 and all thereof are disposed within the confines of the grinding Wheel 1. Leading generally radially outwardly from each of these circular channels 15 through the cylindrical outer mounting surfaces 7 of the mounting hub 6 is a circumferentially spaced row series of liquid coolant delivery passages 16.

In the preferred arrangement illustrated, there is provided a duct means in the form of a tubular liquid coolant delivery conduit 17 for each of the radially inwardly openingcylindrical channels 15. These delivery tubes or conduits 17 may be assumed to extend from a suitable source of liquid coolant supply, such as water, not shown. The conduits .17 all extend axially into their respective annular channels 13 and each thereof has its free discharge end disposed radially adjacent a different one of the circular channels 15 for gravity delivery thereto. Usually the rate of feed of coolant through each of the conduits 17 will be so regulated as to merely drip into their respective cooperating channels 15. The delivery tubes or conduits 17 together with inwardly opening cylindrical channels 15 define coolant conveying means to the circumferentially and axially spaced coolant delivery passages or holes 16.

With the arrangement illustrated, the liquid coolant is delivered to the wall of the grinding Wheel defining the bore thereof at many points closely spaced axially and circumferentially thereof, with the result that the coolant liquid will be disbursed evenly throughout the body of the porous grinding wheel and delivered with great uniformity to the cylindrical outer or peripheral working surface 2 thereof.

My invention has been thoroughly tested and found to be entirely adequate for the accomplishment of the objectives set forth; and, while I have shown a preferred embodiment of my invention, it will be understood that the same is capable of modification without departure from the spirit and scope of the invention as defined in the claims.

What I claim is:

1. In a structure of the class and for the purpose described, a power-driven rotary shaft, a hub structure mounted on the power-driven shaft, said hub structure having a generally cylindrical grinding stone mounting outer surface concentric with the axis thereof, a porous grinding stone having an axial bore receiving the generally cylindrical outer surface of the hub structure, means anchoring the grinding Wheel on the generally cylindrical outer surface of the hub structure for common rotation therewith, the hub structure defining opposed annular channels opening through opposite axially spaced ends of the. hub, said. annular channels, being spaced apart adja: cent the axial center of the hub structure to provide a rigid annular web connecting the radially inner and outer portions; of the hub, a plurality of axially and-l circumferentially spaced liquid coolant passages leading from each such annular channel: outwardly through. the generally cylindrical Outer surface. of the hub structure to the grinding wheel, and a liquid coolant delivery conduit leading to each said annular channel.

2.. The structure defined in claim 1 in which that portion ofthe. hub; structure defining the radially outer walls of said; annular channels are formed to define an axially spaced plurality of generally circular radially inwardly opening channels, and in which there is. a circumferentially spaced series, of said liquid coolant passages leading'from: each of, the last said channels through the outer generally cylindrical surfacev of the hub structure.

3'. The structure defined in claim 2 in further combination with a plurality of liquid coolant delivery conduits leading into each said annular channel, there being one such conduit for each said inwardly opening circular channel, the discharge end of each said conduit being disposed radially opposite a different said generally circular channel.

4. In a structure of the class and for the purpose described, a mounting hub having a generally cylindrical outer surface adapted to be received in the axial bore of a porous grinding wheel, means for anchoring such grinding wheel to the mounting hub for rotation therewith, the. hub having; a plurality of axially-spaced rows of circumferentially-spaced holes through the generally cylindrical outer surface thereof which is normally disposed within the bore of the porous grinding wheel, and a different liquid coolant delivery conduit for each said row of, circumferentially-spaced holes.

5. In a structure of the class and for the purpose set forth, a mounting hub having a generally cylindrical outer surface adapted to be received in the axial bore of a porous grinding wheel, means for anchoring a grinding wheel thus positioned to the mounting hub for common rotation therewith, the hub defining a generally annular internal. channel withinv and generally concentric with the generally cylindrical outer surface thereof, the hub structure defining the outer Wall of said internal annular channel defining an axially spaced plurality of radially inwardly opening generally circular channels, said structure also defining a circumferentially-spaced series of liquid coolant passages leading radially outwardly from each of the last-said channels through the said generally cylindrical outer surface of, the hub, and independent duct means positioned" and arranged to discharge each into a difierent one of said radially inwardly opening channels.

6. In a structure of the class and for the purpose described, a mounting hub having a generally cylindrical outer surface adapted to bev received in the axial bore of a porous grinding wheel, means for anchoring said grinding wheel to said hub for rotation therewith, said hub having a plurality of axially-spaced holes extending radially outwardly through: the outer surface thereof, and structure defining independent coolant conveying means to each of said. axially-spaced holes.

7. In a structure oi the class and for the purpose described, a mounting hubhaving a generally cylindricalouter surface adapted: to, be received in the axial bore of a. porous: grinding wheel, means for anchoring said grinding wheel tosaid hub for rotation therewith, said hub having a plurality of axially-spaced rows of circumferentially-spaced holes extending radially outwardly through the outer surface thereof, and structure defining coolant conveying. means to each ofi said holes, conveying means to; axially-spaced holes being independent of each, other.

References Cited. inthe file of this patent UNITED STATES PATENTS 796,466 Stolzenberg Aug. 8, 1905 2,167,282 Murphy July 25, 1939 2,470,350 Harrington May 17,v 1949 2,546,805 Weiss et al Mar. 27, 1951 2,560,944 Garrison July 17, 1951 2,612,015 Kraft Sept. 30, 1952 

